Dolores Huerta formed the first farmworkers union with Cesar Chavez, stood next to Sen. Robert Kennedy minutes before he was assassinated, inspired Barack Obama’s 2008 “Yes We Can” presidential campaign slogan with her “Sí, Se Puede” rallying cry and has continued her social activism as she approaches her 90th birthday.

Yet she remains unknown to most Americans.

Among Mexican-Americans, however, she’s a civil-rights icon. She draws excitement at rallies for ethnic studies in Arizona, gatherings for women’s rights in Albuquerque, N.M., and even for a cameo appearance at this year’s Academy Awards.

Now the social activist is the subject of “Dolores,” a new PBS documentary from Independent Lens. “Dolores” is scheduled to air on most PBS stations on Tuesday, including at 10 p.m. on KUED Channel 7.

As expected, the documentary covers Huerta’s life as a United Farm Workers leader in California during the late 1960s. It examines her role in fighting against the use of toxic pesticides and for immigrant rights.

But the film also explores her challenges in raising 11 children and the resentment they held for being ignored. The documentary also looks at her love of jazz and her shattered dreams of becoming a dancer.

Director Peter Bratt said the project began after Huerta and guitarist Carlos Santana had a conversation until 3 a.m. during a trip to Hawaii years ago. Santana, a Miles Davis fan, discovered Huerta was a huge fan of bebop legend Charlie Parker.

“I even met Charlie Parker. That’s my claim to fame,” Huerta, 87, told The Associated Press. “There were a lot of things Carlos didn’t know about me.”

That’s when Santana urged Huerta to take part in a documentary to tell her story, Bratt said. Santana is executive producer of “Dolores.”

(George Ballis | Take Stock / The Image Works / courtesy PBS) Dolores Huerta, co-founder of the United Farm Workers, organizes marchers in Coachella, Calif., on March 2, 1969. Huerta's life is chronicled in the documentary "Dolores."

Using archival interviews from Huerta and Chavez, “Dolores” illustrates how Huerta moved from a married woman in a middle-class home to a union activist who gave up a comfortable life to join the fight for equality. When farmworkers or fellow activists would tell her something couldn’t be done or the odds were against them, Huerta would reply, “Sí, Se Puede.” That became the rallying cry for the farmworkers movement.

Angela Davis, Gloria Steinem, Hillary Clinton and “La Bamba” director Luis Valdez all discuss how Huerta evolved from someone pushing a grape boycott to an activist who was denounced by Teamsters, then-future President Ronald Reagan and, later, Fox News personalities like Bill O’Reilly.

But the film goes beyond Huerta’s social-justice activities throughout the years, showcasing the advocate at transformative moments in American history and highlighting her role in defining them.

For example, Huerta is standing next to Robert Kennedy in Los Angeles after his California presidential primary win in June 1968. “Dolores Huerta … who is an old friend of mine,” Kennedy tells the crowd. Huerta helped Kennedy win California’s Mexican-American vote by helping orchestrate a then-unique door-to-door voter registration drive.

Minutes later, Kennedy is shot.

“It was very emotional to watch,” Huerta said after viewing the documentary. “I had to see the film four times before I could get it all to sink in.”

In 2012, Obama finally acknowledged Huerta for her role in the creation of his “Yes, We Can” slogan during his first presidential campaign.

“Dolores was very gracious when I told her that I had stolen her slogan,” said Obama, who then presented her with the Medal of Freedom, the nation’s highest civilian honor. “Knowing her, I’m pleased she left me off easy because Dolores does not play.”

But in spite of her contributions, Huerta has been written out of history — literally. The conservative-leaning Texas State Board of Education voted in 2010 to remove Huerta from third-grade standards over her affiliation with the Democratic Socialists of America organization.

That same year, then-Arizona Gov. Jan Brewer signed a bill banning certain ethnic studies programs after Huerta told a Tucson school that Republicans hated Latinos.

Bratt said he believes the “Dolores” documentary is a way to save her legacy. “People have tried to erase her from history,” Bratt said. “Hopefully, this film is the corrective.”